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MXene‐based Zn‐ion capacitors (ZICs) with adsorption‐type and battery‐type electrodes demonstrate high energy storage and anti‐self‐discharge capabilities, potentially being paired with triboelectric nanogenerators (TENGs) to construct self‐powered systems. Nevertheless, inadequate interlayer spacing, deficient active sites, and compact self‐restacking of MXene flakes pose hurdles for MXene‐based ZICs, limiting their applications. Herein, black phosphorus (BP)‐Zn‐MXene hybrid is formulated for MXene‐based ZIC via a two‐step molecular engineering strategy of Zn‐ion pre‐intercalation and BP nanosheet assembly. Zn ions as intercalators induce cross‐linking of MXene flakes with expandable interlayer spacing to serve as scaffolds for BP nanosheets, thereby providing sufficient accessible active sites and efficient migration routes for enhanced Zn‐ion storage. The density functional theory calculations affirm that zinc adsorption and diffusion kinetics are significantly improved in the hybrid. A wearable ZIC with the hybrid delivers a competitive areal energy of 426.3 µWh cm−2 and ultra‐low self‐discharge rate of 7.0 mV h−1, achieving remarkable electrochemical matching with TENGs in terms of low energy loss, matched capacity, and fast Zn‐ion storage. The resultant self‐powered system efficiently collects and stores energy from human motion to power microelectronics. This work advances the Zn‐ion storage of MXene‐based ZICs and their synergy with TENG in self‐powered systems. [ABSTRACT FROM AUTHOR]

Emerging tribovoltaic nanogenerator (TVNG) technology, which can capture mechanical energy at dynamic semiconductor interfaces and generate instant direct current (DC) outputs, is considered promising to mitigate growing energy demand. However, the unsatisfactory charge excitation and extraction efficiency limit its electrical output stability and even practicability. Here, a novel strategy is proposed to synergistically modulate charge generation and transfer dynamics by integrating ferroelectric and photovoltaic effect with tribovoltaic effect, and thus a multi‐effect coupled Schottky TVNGs is, for the first time, developed. Research indicates that such coupling mechanism involving ferroelectric polarization, photoexcitation, and triboelectricity can allow TVNGs to jointly collect light and mechanical energy to excite more charges, and meanwhile, incorporation of strong electric fields can also be induced by controlled polarization to assist Schottky junction in modulating separation/extraction efficiencies of these charges. Ultimately, this multi‐effect coupled devices deliver impressive DC output of 7.3 V and 69.8 µA, outperforming similar coupled Schottky junction TVNGs. Besides that, its feasibility for multifunctional sensing and photodetection is also demonstrated. This study proposes an effective strategy for modulating performance while extending its functionality, which can expedite the development and potential application of advanced TVNGs. [ABSTRACT FROM AUTHOR]

Vegetation communities can drastically influence the hydrodynamic characteristics of the overland flow, change the overland flow resistance mechanism, and regulate soil erosion. To investigate the effect of grass-shrub vegetation and litter combinations on overland flow resistance, simulated rainfall experiments were carried out. The experiments involved a 15° gradient slope, five rainfall intensities (I = 60–120 mm h−1), five grass-shrub coverages (Cgs), and six litter volumes (Cl). The results showed that the mean values of form resistance under Cgs = 15%–75% ranged from 0.195 to 1.775, and the mean values of form resistance under Cl = 5–25 g m−2 ranged from 0.609 to 2.160. The form resistance of grass-shrub slopes with the addition of litter was 1.82–12.47 times higher than that under a single grass-shrub cover. The order of magnitude of the factors influencing the slope form resistance coefficients of the grass-shrub + litter was Cl > Cgs > Cl × Cgs > I. With varying vegetation kinds and coverage rates, I had diverse effects on form resistance. The resistance superposition principle does not hold under combined vegetation cover conditions. The degree of difference (Δ f form ) in form resistance was inversely proportional to I and directly proportional to Cl. Through dimensional and multiple nonlinear regression analyses, a general model for calculating form resistance was established (Adj. R2 = 0.99, NSE = 0.97). Theoretically, the results of this study can be used to evaluate soil and water conservation during vegetation community succession and restoration. [ABSTRACT FROM AUTHOR]

The commercial utilization of Zn metal anodes with high plating capacity is significantly hindered by the uncontrolled growth of dendrites and associated side reactions. Herein, a robust artificial ion‐sieving MXene flake (MXF)‐coating layer, with abundant polar terminated groups, is constructed to regulate the interfacial Zn2+ deposition behavior. In particular, the fragmented MXF coupled with in situ generated quantum dots not only has strong Zn affinity to homogenize electric fields but also generates numerous zincophilic sites to reduce nucleation energy, thus securing a uniform dendrite‐free surface. Additionally, the porous coating layer with polar groups allows the downward diffusion of Zn2+ to achieve bottom‐up deposition and repels the excessive free water and anions to prevent parasitic reactions. The ion‐sieving effect of MXF is firmly verified in symmetric cells with high areal capacity of 10–40 mAh cm−2 (1.0 mA cm−2) and depth of discharge of 15%–60%. Therefore, the functional MXF‐coated anode manifests long‐term cycling with 2700 h of stable plating/stripping in Zn||Zn cell. Such rational design of MXF protective layer breaks new ground in developing high plating capacity zinc anodes for practical applications. [ABSTRACT FROM AUTHOR]

Objective: Currently, there is no simple and valid method to predict the length and size of the native anterior cruciate ligament (ACL) in each adult patient who will undergo ACL reconstruction. This study aimed to develop an imaging prediction method that can predict the length and size of ACL grafts using the intact posterior cruciate ligament (PCL), in order to enhance the graft preparation individualized sizing. Methods: Three hundred and nineteen patients aged 18 years or older who underwent magnetic resonance imaging (MRI) of the knee at an orthopaedic clinic between September 9, 2021, and February 5, 2023, were included. The length, sagittal diameter, and coronal diameter of the ACL and PCL were measured in all patients, and F‐test were performed to explore linear relationship between ligament measurements. Results: Equations were established to predict a variable of the native ACL for the corresponding variable of the intact PCL (i.e., sagittal diameter of the ACL = 4.32 + 1.08 × sagittal diameter of the PCL, and coronal diameter of the ACL = 2.45 + 0.59 × coronal diameter of the PCL, length of the male ACL = 10.92 + 0.64 × length of the male PCL, length of the female ACL = 11.76 + 0.58 × length of the female PCL) (R2 = 0.532; R2 = 0.417; R2 = 0.488; R2 = 0.509; respectively). Conclusions: The length and size of the intact PCL in cases without PCL buckling are predictors of the length and size of the native ACL in adults, respectively. The use of this information to optimize graft diameter may lower the rates of ACL graft failure in the future. [ABSTRACT FROM AUTHOR]

In space exploration activities, a large amount of materials needs to be carried, which limits the sustainable development of exploration activities. In‐situ resource utilization (ISRU) is an important means to realize resource recycling and continuous space exploration, which converts space resources into oxygen and hydrocarbon fuels. The traditional ISRU in outer space mainly uses high temperature and high pressure to electrolyze water or reduce CO2, having problems such as low conversion efficiency, high energy consumption, and excessive equipment volume. Here, an electrochemical catalytic synthesis technology based on a microfluidic device is proposed, which can convert H2O and CO2 into O2 and organic matter by electrocatalytic method at room temperature and achieve efficient energy and matter conversion. The gas‐liquid mixing and electrochemical reaction were analyzed. A mathematical model of gas‐liquid two‐phase mixing and microfluidic chemical reaction was established. The research results demonstrate the reliability and efficiency of the microfluidic reaction device designed in this paper for ISRU. [ABSTRACT FROM AUTHOR]

Precipitation products play an important role in monitoring rainstorm processes. This study takes a rare historical event of extreme, heavy precipitation that occurred in Henan Province, China, in July 2021 as a research case. By analyzing the distribution of the spatial and temporal characteristics of precipitation errors, using a probability density function of the occurrence of precipitation and the daily variation pattern, we assess the capability of a radar precipitation estimation product (RADAR), satellite precipitation products (IMERG and GSMAP), a reanalysis product (ERA5) and a precipitation fusion product (the CMPAS) to monitor an extreme rainstorm in the Henan region. The CMPAS has the best fit with the gauge observations in terms of the precipitation area, precipitation maximum and the evolution of the whole process, with a low spatial variability of errors. However, the CMPAS slightly underestimated the precipitation extremum at the peak moment (06:00–08:00). The RADAR product was prone to a spurious overestimation of the originally small rainfall, especially during peak precipitation times, with deviations concentrated in the core precipitation area. The IMERG, GSMAP and ERA5 products have similar performances, all of which failed to effectively capture heavy precipitation in excess of 60 mm/h, with negative deviations in precipitation at mountainfront locations west of northern Henan Province. There is still a need for terrain-specific error revisions for areas with large topographic relief. By merging and processing precipitation data from multiple sources, the accuracy of the CMPAS is better than any single-source precipitation product. The CMPAS has the characteristic advantage of high spatial and temporal resolutions (0.01° × 0.01°/1 h), which play a positive role in precipitation dynamic monitoring, providing early warnings of heavy rainfall processes and hydrological application research. [ABSTRACT FROM AUTHOR]

The fast OH− transfer between hydroxide layers is the key to enhancing the charge storage efficiency of layered double hydroxides (LDH)‐based supercapacitors (SCs). Constructing interlayer reactive sites in LDH is much expected but still a huge challenge. In this work, CdS nano‐dots (NDs) are introduced to interlayers of ultra‐thin NiFe‐LDH (denoted CdSinter.‐NiFe‐LDH), promoting the interlayer ions flow for higher redox activity. The excellent performance is not only due to the enlarged layer spacing (from 0.70 to 0.81 nm) but also stems from anchored interlayer reactive units and the undamaged original layered structure of LDH, which contribute to the improvement of OH− diffusion coefficient (1.6 × 10−8 cm2 s−1) and electrochemical active area (601 mF cm−2) better than that of CdS NDs on the surface of NiFe‐LDH (2.1 × 10−9 cm2 s−1 and 350 mF cm−2). The champion CdSinter.‐NiFe‐LDH electrode displays high capacitance of 3330.0 F g−1 at 1 A g−1 and excellent retention capacitance of 90.9% at 10 A g−1, which is better than the NiFe‐LDH with CdS NDs on the surface (1966.6 F g−1). Moreover, the assembled asymmetric SCs (ASC) device demonstrate an outstanding energy density/power density (121.56 Wh kg−1/754.5 W kg−1). [ABSTRACT FROM AUTHOR]

Owing to the flexible adjustability of laminates, layered double hydroxides (LDHs) can achieve enhanced conductivity and capacitance. However, the regulation of interlayer activity is a great challenge because of the unconquerable charge repulsion between laminates. Herein, a dual‐activity design of LDHs is uniquely realized, including laminate defects and interlayer ZnS quantum dots (QDs). Via pre‐embedding Zn2+ and controllable vulcanization, ZnS‐QDs interpenetrate between CuCo‐LDH layers, exposing abundant active sites and widening the layer spacing. Meanwhile, sulfur replaces part of the oxygen on the laminates to form rich oxygen vacancies (CuCo‐LDH‐S), which does not damage the layered spatial structure and ensures the fast ions/electron transport. Theoretical calculations indicate that the new active centers exhibit higher charge density as compared to CuCo‐LDH. Moreover, the copper foam directly provides copper source to ensure that CuCo‐LDH‐S/ZnS‐QDs present a 3D self‐supporting structure with ultrastability. Hence, it delivers an ultrahigh capacitance of 7.82 F cm−2 at 2 mA cm−2 and 4.43 F cm−2 at 20 mA cm−2. The hybrid supercapacitors display an outstanding energy density of 299 µWh cm−2 at power density of 1600 µW cm−2, with outstanding capacitance retention of 102.3% and coulomb efficiency of 96.2% after 10 000 cycles. [ABSTRACT FROM AUTHOR]

Human beings need abundant material support and energy supply in their exploration of the universe. The sustainable supply of materials is an important condition for long-term space exploration. In situ resource utilization technology (ISRU) is an important way to realize the sustainable development of space exploration, which uses the abundant raw materials in outer space to transform energy and materials. In this paper, a microfluidic reaction device based on in situ resource utilization is designed, which converts H2O and CO2 into O2 and organic matter through photoelectrocatalysis. The flow and mixing process of gas-liquid two-phase flow was studied, and both the characteristics of mass transfer and the chemical reaction of fluids in the microchannel were studied. The dynamic process of the fluid-in-microchannel chemical reaction was expounded, and a prediction model of the volumetric mass transfer coefficient was proposed. The results show that the mass transfer coefficient of the chemical reaction is affected by the gas-liquid flow characteristics, and the mass transfer affects the rate of the chemical reaction. The material conversion of in situ resources by using the microchannel device can improve efficiency and accurately control the reaction products. [ABSTRACT FROM AUTHOR]